title: Classification of iRBD and Parkinson's disease patients based on eye movements during sleep.
abstract: Patients suffering from the sleep disorder idiopathic rapid-eye-movement sleep behavior disorder (iRBD) have been observed to be in high risk of developing Parkinson's disease (PD). This makes it essential to analyze them in the search for PD biomarkers. This study aims at classifying patients suffering from iRBD or PD based on features reflecting eye movements (EMs) during sleep. A Latent Dirichlet Allocation (LDA) topic model was developed based on features extracted from two electrooculographic (EOG) signals measured as parts in full night polysomnographic (PSG) recordings from ten control subjects. The trained model was tested on ten other control subjects, ten iRBD patients and ten PD patients, obtaining a EM topic mixture diagram for each subject in the test dataset. Three features were extracted from the topic mixture diagrams, reflecting "certainty", "fragmentation" and "stability" in the timely distribution of the EM topics. Using a Naive Bayes (NB) classifier and the features "certainty" and "stability" yielded the best classification result and the subjects were classified with a sensitivity of 95 %, a specificity of 80% and an accuracy of 90 %. This study demonstrates in a data-driven approach, that iRBD and PD patients may exhibit abnorm form and/or timely distribution of EMs during sleep.
authors.forename: Julie A E
authors.initials: JA
authors.lastname: Christensen
authors.forename: Henriette
authors.initials: H
authors.lastname: Koch
authors.forename: Rune
authors.initials: R
authors.lastname: Frandsen
authors.forename: Jacob
authors.initials: J
authors.lastname: Kempfner
authors.forename: Lars
authors.initials: L
authors.lastname: Arvastson
authors.forename: Soren R
authors.initials: SR
authors.lastname: Christensen
authors.forename: Helge B D
authors.initials: HB
authors.lastname: Sorensen
authors.forename: Poul
authors.initials: P
authors.lastname: Jennum
mesh_terms: D000368:Aged; D016477:Artifacts; D001499:Bayes Theorem; D016022:Case-Control Studies; D004585:Electrooculography; D005133:Eye Movements; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000145:classification / Q000503:physiopathology*; D017286:Polysomnography; D020187:REM Sleep Behavior Disorder / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology*; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D012890:Sleep